Loading device



y 3, 1951 M. A. HOLLENGREEN ET AL 2,559,430

LOADING DEVICE Filed Dec. 8, 1948 Gttorneg these have met with any greatsuccess.

Patented July 3, 1951 UNITED STATES PATENT OFFECE LOADING DEVICE MilburnA. Hollengreen and William E. Happel,

Waynesboro, Pa., assignors to Landis Tool Company, Waynesboro, Pa.

Application December 8, 1948, Serial No. 64,156

6 Claims.

This invention relates to a loading apparatus and method for introducingwork pieces, such as anti-friction bearing rings, into a centerlessgrinding throat.

Previous methods and devices for performing this function usuallyrequired that the work be pushed into the grinding throat eithermanually or by a power-operated pushing device. None of One essentialcharacteristic of a device of this type is that it feeds the Work to thegrinding throat at substantially the same rate that the regulating wheelfeeds the work through the grinding throat. We propose to meet thisrequirement in a manner which is directly opposite to that used inprevious attempts to make loading devices for this kind of work. Insteadof pushing the work to the grinding throat, we propose to use thefeeding action of the regulating wheel to pull the work into the throatas well as to feed it through the throat.

It is, therefore, an object of this invention to provide means wherebythe work pieces may be held closely face to face both before and afterentering the grinding throat.

A further object is to magnetize the work pieces before introducing theminto the grinding throat.

A further object is to provide means for demagnetizing the work piecesafter they leave the grinding throat.

The drawing shows the conventional centerless grinding throat providedbetween a peripherally opposed grinding wheel In and regulating wheel H.The work pieces I2 are supported between the wheels in the conventionalmanner on a Work rest blade (not shown). A magnetizing coil I5 ismounted at the entrance end of the grinding throat and may be energizedby any suitable source of direct current. A tube l8 serves to guide thework pieces through said coil and toward said grinding throat.

The control wheel is wider than the grinding wheel and its operativesurface extends beyond that of the grinding wheel at the entrance end ofthe grinding throat. A spring pressed roller I1 is mounted opposite thisportion of the control wheel and above the center of the work to holdthe work against the work rest and the control wheel. When a series ofwork pieces is started toward the throat, this action of roller llcauses rotation of the work prior to entering the throat. After the workenters the throat, all the magnetized pieces in or out of the throatcontinue to rotate due to the action of the grinding and control wheels.Said roller is still needed to hold the work on the rest prior toentering the throat.

A demagnetizing coil !6 is mounted at the exit end of the grindingthroat and may be energized by any suitable source of alternatingcurrent. A tube l9 conducts finished work pieces from the grindingthroat through said demagnetizing coil I6.

When coil 15 is energized and a series of work pieces are passedtherethrough, said work pieces become magnetized and adhere to oneanother. To start the grinding operation, the operator pushes the workpieces through the magnetizing coil until the first one enters thegrinding throat. A certain amount of feeding action is also provided bycoil 15 in that it tends to hold all the work pieces within the magneticfield in a predetermined position. When this condition is disturbed,such as by adding new pieces, the magnetic field tends to maintain itsbalance and in so doing advances the succession of work pieces towardthe grinding throat.

Thereafter, the regulating wheel takes up the rotation and feeding ofthe work; and the work pieces outside the throat are rotated and movedendwise along with those in the throat. Thus, it may be said that theregulating wheel pulls the work into the throat as well as causes it topass through the throat.

After the work has been ground, it passes from the grinding throatthrough the demagnetizing coil. As the work leaves the demagnetizingcoil, it is again separated into individual pieces. This method causesthe work pieces to be held square relative to one another beforeentering the grinding throat as well as during the passage throughthegrinding throat. When so held, there is very little chance, if any,of the works being ground tapered.

We claim:

1. In a centerless grinding machine, peripherally opposed grinding andcontrol wheels, a work rest for supporting work pieces in operativerelation to said wheels, means for magnetizing work pieces beforeintroducing them between said wheels, said magnetizing means beingeffective to advance said work pieces toward said wheels as additionalwork pieces are added and. causing them to adhere to one another wherebyto hold them square with each other and cause them to rotate as a unitwhen acted upon by the control wheel and the grinding wheel during thegrinding operation.

2. In a centerless grinding machine, peripherally opposed grinding andcontrol wheels, a work rest for supporting work pieces in operativerelation to said wheels, means for magnetizing work pieces beforeintroducing them between said wheels, said magnetizing means beingeffective to advance said work pieces toward said wheels as additionalwork pieces are added and causing them to adhere to one another wherebyto hold them square with each other and with the grinding wheel duringthegrinding operation, means for tilting said control wheel to move saidWork pieces as a unit past said grinding wheel,

and means for demagnetizing said work pieces-asthey pass from betweensaid wheels.

3. The method of introducing ringlike" work pieces into the throat ofa-centerless;grinding machine having peripherally :oppos'ectgrinding andcontrol wheels and a work rest for supporting work pieces in operative.relation to said wheels and in which the axis of the control wheelation, introducing said work pieces from said magnetizing means intosaid grinding throat, feeding said work pieces through said grindingthroat as a unit by the feeding action of the control wheel, andthereafter demagnetizing said work pieces.

5. In a centerless grinding machine, periphxerallyopposed grinding andcontrol wheels, a

work rest for supporting work pieces in operative relation to saidwheels, means for magnetizing :work pieces before introducing thembetween said "wheels comprising a magnetizing coil adjacent theentranceto the grinding throat formed between-said .wheels,imeans for passing asuccession of workpieces. through said coil and into the I: grindingthroat, this movement being assisted by the vaction of .the. coil incausing the succession of is tilted relative to the axis of the grindingwheel which consists in magnetizing said work pieces so that:they adhereto one anotheraand thereby ;:produce' the efiect "of a 'singleelongated'work piece which may be held substantially: square with .2 saidgrinding" wheel during a. grinding, operation, -.-.-advancingtheworkpieces. axially toward thegrinding throat by the action of themagnetizing means, feeding said work pieces through. the

.throat.:as a unitby the action of the-control wheel, and. thereafter*demagnetizingv said work pieces.

a 4;. The: method of.introducing t-ringlike work ,piecesinto the throatof a centerless grinding machine having; peripherally opposed grindingand control wheels and a work-rest-for supportwing'work piecesinoperative relation to said i :wheelsfand in-which the axis of thecontrol'wheel is tilted relative to the 'axis' of the grinding wheel=which consists in magnetizing said workpieces "-so that theyadhere to.one another and thereby producethe effect ofa single elongated workpiece which may .-:-be-held substantiallyqsquarewithsaid-grindingwheelduring a grinding pperwork pieces to advance eachtime additional work -.pieces are added, said coil also causing saidwork pieces to become magnetized so as to adhere to one another; whereby:they varer-caused' tocrotate as a unit when acted upon by thegrindingand a control Wheels.

6. In a machine tool in whicharough'work pieces are introduced at onepoint andpareidischarged .in .finished condition .at another point,.means for :holding ringlikev-memberssin position for a machiningoperation;comprising. a .guide means for directing said work piecesintothe :machine; a. magnetizing .coil surrounding said.

; guide means for magnetizing said work pieces so V. that-they willadhere torone anotheriduringthe machining operation, additional guide.means-at the discharge point on theimachine for conducting finished workpieces away from the machine,

.' and a .coil surrounding said guide-means for demagnetizing saidwork-pieces.

r .MILBURN A. HOILENGREEN;

VIILLIAM HAPPEL.

. "No references cited.

